Currently there are four basic concepts used for handling a bale during processing:
1. TRAVELING TABLE
With this design one or more chains travel over a generally horizontal table. The chains may have slats or spikes attached to them to engage in a bale being processed. The bale processing rotor is located at one end of the table. The table and rotor may be separated by generally vertical bars spaced such that rotor hammers are allowed to pass between the bars and come in contact with the bale being processed. Machines of this sort are designed to process round bales of varying diameters.
In the use of such a machine a bale is placed on the table and the chains travel in a direction to move the bale towards the rotor. The bale engages the vertical bars to limit its movement towards the rotor. Because the chains are continuously advancing, the bale is forced to roll, thus bringing new bale material to the rotor. As bale processing continues, the diameter of the bale is gradually reduced until the entire bale has been fed to the rotor.
Problems can occur with this type of unit when attempting to process old bales which have flattened out. These do not roll well and can cause problems of uneven feeding of the bale into the rotor. In some circumstances, the bale can get into a position in which the rotor hammers are no longer in contact with the bale and the chains are unable to engage the bale sufficiently well to rotate it to expose new material to the rotor. This type of processor can not process square bales, loose hay or other materials.
2. SUPPORT ROLLERS
This type of machine has two rollers mounted above and on opposite sides of the bale shredding rotor assembly. The rollers may have a number of spikes which engage a bale being processed. Between these rollers and the rotor are a number of curved bars arranged to allow rotor hammers to project through the bars into contact with the bale. The bars prevent too much material from coming into contact with the rotor.
To shred a bale with this type of unit, a bale is positioned on the two rollers. At least one of these rollers is driven to cause the bale to rotate. As the bale rotates, new material is brought into contact with the rotor hammers. As processing continues, the diameter of the bale is gradually reduced until the entire bale has been fed through the machine.
This type of machine also has problems with shredding bales that have gone out of round. In some cases the rollers are unable to rotate the bale, thus preventing the completion of the processing operation. Soft or loosely packed bales can also pose problems in that they tend to fall apart before they can be fully processed. This causes uneven feeding of material to the rotor. This type of machine can not process square bales, loose hay or other materials.
3. ROTATING TUB
The rotating tub machine is also designed to process only round bales. It consists of a loading mechanism that grasps the bale and rotates it onto a horizontal table. A portion of the table is open allowing the rotor hammers to come into contact with the bale.
In this type of machine, the bale is processed with its axis in the vertical orientation, unlike the other machines where the bale axis is horizontal. The loading mechanism also functions as the device that rotates the bale. The rotor hammers project above the plane of the table, thus coming into contact with the bale. As the bale tub rotates the bale on the table, new material is brought into contact with the rotor. As processing continues, the bale length is reduced until the entire bale has been fed through the rotor.
This machine is not as sensitive to the condition or shape of the bale being processed. However, very large bales or bales that are badly deformed can cause problems with loading and processing. Because the loading mechanism is also used to process the bale, it is not possible for a second bale to be carried while a bale is being processed as is the case with other machines. It is not possible to process square bales or loose materials with this machine.
4. OSCILLATING TUB
This type of machine is intended to be able to process round and square bales. It consists of a horizontal table positioned above the rotor assembly. There is an opening in the table which allows the hammers of the rotor to protrude above the plane of the table, thus contacting the bale. A series of horizontal bars are positioned across the opening to prevent too much material from contacting the rotor. An open bottom enclosure to house the bale rests on the surface of the table. With a bale loaded into the tub, the tub moves in a horizontal direction perpendicular to the rotor and pushes the bale across the opening in the table, thus exposing new material to the hammers of the rotor. Once the tub is moved to its limit of travel in one direction, it is reversed and the process is repeated.
Theoretically, this machine can process round bales of varying diameter as well as square bales and loose material. The machine should in theory not be susceptible to the condition of the material being processed. This is not found to be universally true.
The tub of this machine must be sized to accommodate the largest diameter of round bale likely to be encountered. In the case of old, deformed bales, this could be eight feet or more. When a smaller diameter bale is processed with such a machine, a problem of uneven feeding occurs. For example, if a five foot diameter bale is placed in an eight foot tub, a total of three feet of clearance exists between the walls of the tub and the bale. As the bale is processed, the tub moves to one side pushing the bale in that direction. When the tub reaches its limit of travel in that one direction, it reverses. There is, at this time, a three foot opening between the tub wall and the surface of the bale. This space must be closed in order for the bale to begin its movement in the opposite direction. During this time, very little new material is made available to the rotor hammers, thus causing uneven shredding of the bale. A similar problem occurs when attempting to process a square bale, as its cross-section is smaller than typical round bales.
Another problem has been noted with this type of machine. As the bale is moved across the opening in the table, part of the bale weight is supported by the horizontal bars located across the rotor opening. The rotor hammers are unable to remove the material immediately above the crossbars. With densely packed bales, the result is that channels are cut in those portions of the bale exposed to the hammers, while the portions immediately above the crossbars remain untouched. Once all of the material between the crossbars has been removed, no further shredding action occurs, as the entire bale weight is now supported by the crossbars. As the bale moves back and forth, it seems to return along the same path, thus not correcting the problem. This can result in a need to manually remove or reposition the bale in order to complete the shredding operation.
With this machine, the side to side motion used to process the bale results in significant shifts in the center of gravity of the unit. This can make the machine unstable when processing bales on uneven terrain. This can be rectified with a wide wheel track, but this in turn is disadvantageous in that it makes the machine more difficult to maneuver.
The present invention is concerned with a novel bale processing apparatus that mitigates the problems of the prior art.